Gale Warning 551, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
512 PM AKDT Wed Sep 24 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
Tonight through Saturday)...

Discussion:

A large low is in the northwestern Gulf of Alaska this afternoon.
The occluded front can be seen on satellite imagery wrapped up
around the low and along the north Gulf coast and Panhandle. A
distinct dry slot between the frontal arms is testimony to the
strength of the low even though is has largely lost its upper
level support with the jet stream running well south of it. This
low is bringing widespread Gale-force winds from the Alaska
Peninsula in northwesterly winds to the north Gulf coast with
easterly winds. This low will weaken significantly overnight
though the north Gulf coast will continue to see occasional
moderate or heavy rainfall into tomorrow morning.

The weather then gets a little more interesting for the next two
days as an upper level wave, which can be seen best on GOES-18
Airmass imagery, is north of Adak and will move southeastward
overnight. There is cold air aloft associated with this wave and
it will cross the Alaska Peninsula Thursday morning and dive south
of Kodiak by afternoon. As the wave does this, it will tighten
the gradient over the Alaska Peninsula and Kodiak Island
while winds over most of Southcentral Alaska will be on their way
down. While this shortwave and resultant lee-side low will not
impact most of Southcentral, what it does do, is set up the track
for yet another, stronger, upper level wave to move into the area.
This next wave has been giving the models fits for the past few
days with very little model agreement or continuity between runs.
However, the 12Z GFS and NAM are converging on a reasonable
solution which should move the 500 mb low from the northern Bering
Sea Thursday night to Kodiak Island Friday night and then into
the central Gulf Saturday afternoon. The exact track of this upper
level low will be important as areas north of it is where most of
the precipitation will occur. This more progressive solution will
also allow temperatures aloft to cool quicker than it looked like
earlier which means snow will make it farther down the mountains
for Friday night into Saturday morning. At this time, only the
higher highway passes and the upper hillside in Anchorage look to
see a chance for snow to mix that far down, but it will be
something to keep watching as this system develops. This is a
pattern where the forecast can change quickly as changes in the
track of the upper level low may have a big impact on the
resultant weather.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3)...

Gale force winds with storm force gusts will continue across the
southern Alaska Peninsula and Eastern Aleutians this afternoon,
diminishing this evening. Widespread small craft winds will
continue over the next several days across the central/eastern
Bering Sea. The next impactful system will be dropping south out
of eastern Russia to skirt along the Southwest Coast. There
remains a fair amount of uncertainty with the exact low track and
its speed as it travels along the coast, though there is a good
chance for precipitation along the coast and strong nearshore
winds. There is moderate confidence that a core of strong
northerly winds will move over Nunivak Island early Friday
morning. A swath of cold air advects south across the Bering Sea
and Southwest Alaska Thursday through Saturday as the low moves
south, allowing for gales and gusty conditions to redevelop in the
central/eastern Bering, tracking across the Pribilof Islands and
through the gaps and passes south of the Alaska Peninsula.

-CL

&&

.LONG TERM FORECAST (Days 4 through 7: Sunday through Wednesday)...

Perhaps a quieter weather pattern in store for Southwest and
Southcentral Alaska Sunday into next week as high pressure builds
over the region. In the wake of a departing low over the Gulf of
Alaska precipitation chances should wind down along with
diminishing winds. Weak northerly flow over Southcentral Alaska
and clearer skies may also result in some colder overnight low
temperatures. Further west, gusty northerly winds may linger for a
hair longer across the Eastern Aleutians and Alaska Peninsula,
but those too should taper off by the start of the work week.
Cooler temperatures will continue for Southwest Alaska, though
that does not come as a surprise for this time of year.

The main forecast challenge continues to be with what happens to
the remnants of Typhoon Neoguri, currently spinning idly over the
West Pacific. Due to a lack of meaningful steering flow, models
are struggling with resolving the future track of Neoguri. The GFS
continues to bring Neoguri into the Aleutian Chain on Monday of
next week, picked up by a passing upper trough. The ECMWF is
slower and much further south. Regardless of its eventual track,
even more uncertainty lingers with if Neoguri will see any
resurgence in intensity as an extratropical cyclone. It's too far
out to expect any semblance of an accurate forecast, but will be
good to continue monitoring its progression and future model
guidance. Keep an eye on the forecast in the event that it does
bring elevated winds to the Aleutians and possibly Southwest
Alaska later in the period.

BL

&&
.AVIATION...

PANC...Strong low level winds coming across the Kenai and Chugach
Mountains will continue to produce downslope drying at the
terminal along with VFR ceilings. The strength of the winds and
downslope will weaken this evening as an occluded front dissipates
along the Gulf coast. This could allow a few sprinkles to make it
over the mountains, but with dry air near the surface ceilings
will remain safely in the VFR category. Light northerly winds will
persist.

-SEB

&&